efi_switch_mm() is a wrapper around switch_mm() which saves current's
->active_mm, sets the requests mm as ->active_mm and invokes
switch_mm().
I don't think that task_lock() is required during that procedure. It
protects ->mm which isn't changed here.
It needs to be mentioned that during the
> > Because local_save_flags() does not disable interrupts??
>
> now that you say so, it does make sense…
>
> > > Anyway, I would still like to get rid of task_lock() in efi_switch_mm().
> > > Any objections to that?
> >
> > No, not at all.
> okay.
I don’t have any either and thanks for the
On 2018-07-24 18:19:15 [+0200], Ard Biesheuvel wrote:
> > Regarding the workqueue in commit 3eb420e70d87 ("efi: Use a work queue
> > to invoke EFI Runtime Services"). The efi_call_virt_pointer() function
> > uses local_save_flags() while invoking the EFI function. Why does commit
> > message say
On 24 July 2018 at 18:02, Sebastian Andrzej Siewior
wrote:
> On 2018-07-24 17:32:14 [+0200], Ard Biesheuvel wrote:
>> Please refer to what has been queued up in tip:efi/core. Sai has
>> implemented a work queue for EFI calls so they occur from a kernel
>> thread, and the mixed mode locking has
On 2018-07-24 17:32:14 [+0200], Ard Biesheuvel wrote:
> Please refer to what has been queued up in tip:efi/core. Sai has
> implemented a work queue for EFI calls so they occur from a kernel
> thread, and the mixed mode locking has been fixed as well.
I see commit 83a0a2ea0b99 ("efi/x86: Prevent
On 24 July 2018 at 17:29, Sebastian Andrzej Siewior
wrote:
> On 2018-07-24 17:00:09 [+0200], Peter Zijlstra wrote:
>> On Tue, Jul 24, 2018 at 04:35:09PM +0200, Sebastian Andrzej Siewior wrote:
>> > I doubt that there any need to set ->active_mm. It is used by the
>> > scheduler to keep track of
On Tue, Jul 24, 2018 at 04:35:09PM +0200, Sebastian Andrzej Siewior wrote:
> I doubt that there any need to set ->active_mm. It is used by the
> scheduler to keep track of the "currently used mm" so it can reuse one
> for the kernel thread which does not own one and take a reference on it
> so it
During invocations of EFI functions efi_switch_mm() is used to set the
active mm to borrow a different MM for a while. This used for instance
by efi_call_virt_pointer():
efi_call_virt_pointer()
- arch_efi_call_virt_setup()
- preempt_disable()
-
